Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:cond-mat/0102425 · Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics

Latent heat calculation of the three-dimensional q=3, 4, and 5 Potts models by the tensor product variational approach

Andrej Gendiar, Tomotoshi Nishino

Published Apr 10, 2002• 28 citations
arXivHTMLPDF

Abstract

Three-dimensional (3D) q-state Potts models (q=3, 4, and 5) are studied by the tensor product variational approach, which is a recently developed variational method for 3D classical lattice models. The variational state is given by a 2D product of local factors, and is improved by way of self-consistent calculations assisted by the corner transfer matrix renormalization group. It should be noted that no a priori condition is imposed for the local factor. Transition temperatures and latent heats are calculated from the observations of thermodynamic functions in both ordered and disordered phases.

DOI
10.1103/physreve.65.046702

Related papers

1Two-Dimensional Tensor Product Variational Formulation

Tomotoshi Nishino, Yasuhiro Hieida, Kouichi Okunishi +2 more

We propose a numerical self-consistent method for 3D classical lattice models, which optimizes the variational state written as two-dimensional product of tensors. The variational partition function is calculated by the corner transfer matrix renormalization group (CTMRG), which is a variant of the density matrix renormalization group (DMRG). Numerical efficiency of the method is observed via its application to the 3D Ising model. Variational states represented as products of local tensols have been used widely for calculating the ground-state energy in one-dimensional (1D) quantum systems and the free energy in two-dimensional (2D) classical statistical systems. In 1941 Kramers and Wannier calculated a lower bound of the partition function of the 2D

•Jan 1, 2000•59 citations

Two-Dimensional Tensor Product Variational Formulation

T. Nishino, Y. Hieida, K. Okunishi +3 more

We propose a numerical self-consistent method for 3D classical lattice models, which optimizes the variational state written as a two-dimensional product of tensors. The variational partition function is calculated using the corner transfer matrix renormalization group (CTMRG), which is a variant of the density matrix renormalization group (DMRG). The numerical efficiency of the method is exemplified in its application to the 3D Ising model.

arXiv:cond-mat/0011103•Progress of Theoretical Physics•Mar 1, 2001•152 citations

Numerical Latent Heat Observation of theq=5Potts Model

Tomotoshi Nishino, Kouichi Okunishi

Site energy of the five-state ferromagnetic Potts model is numerically calculated at the first-order transition temperature using corner transfer matrix renormalization group (CTMRG) method. The calculated energy of the disordered phase $U^{+}$ is clearly different from that of the ordered phase $U^{-}$. The obtained latent heat $L = U^{-} - U^{+}$ is 0.027, which quantitatively agrees with the exact solution.

arXiv:cond-mat/9711214•Journal of the Physical Society of Japan•Apr 15, 1998•15 citations

Estimation of the magnetic critical exponent by Tensor Product Variational Approach

Andrej Gendiar, Tomotoshi Nishino, René Derian

A variational problem for three-dimensional (3D) classical lattice models is considered with trial state given by two-dimensional (2D) uniform product of local variational weights. This approach, the tensor product variational approach (TPVA), has been applied to 3D classical models (the Ising and the Potts models). We consider a way of estimating the magnetic critical exponent $β$ for the simple 3D Ising model assuming a functional form of the spontaneous magnetization in the off critical region, where the TPVA provides reliable data.

arXiv:cond-mat/0412192•Dec 8, 2004•2 citations

First-order to second-order phase transition changeover and latent heats of q -state Potts models in d =2,3 from a simple Migdal-Kadanoff adaptation

H. Yağız Devre, A. Nihat Berker

The changeover from first-order to second-order phase transitions in q-state Potts models is obtained at q_{c}=2 in spatial dimension d=3 and essentially at q_{c}=4 in d=2, using a physically intuited simple adaptation of the Migdal-Kadanoff renormalization-group transformation. This simple procedure yields the latent heats at the first-order phase transitions. In both d=2 and 3, the calculated phase transition temperatures, respectively compared with the exact self-duality and Monte Carlo results, are dramatically improved. The method, when applied to a slab of finite thickness, yields dimensional crossover.

arXiv:2202.01528•Physical review. E•May 16, 2022•14 citations

Stable Optimization of Tensor Product Variational Functions

Andrej Gendiar, Nobuya Maeshima, Tomotoshi Nishino

We consider a variational problem for three-dimensional (3D) classical lattice models, where the trial state is given by a uniform 2D product of local factors. Maximization of the variational partition function draws a self-consistent equation for the local factor. We propose a stable algorithm to solve the equation numerically when the variational function contains many degrees of freedom. Numerical stability and efficiency of the new algorithm is examined through its application to the 3D Ising model. 1

•Mar 19, 2003•0 citations
Three-dimensional (3D) q-state Potts models (q=3, 4, and 5) are studied by the tensor product variational approach, which is a recently developed variational method for 3D classical lattice models. The variational state is given by a 2D product of local factors, and is improved by way of self-consistent calculations assisted by the corner transfer matrix renormalization group. It should be noted that no a priori condition is imposed for the local factor. Transition temperatures and latent heats are calculated from the observations of thermodynamic functions in both ordered and disordered phases.
We propose a numerical self-consistent method for 3D classical lattice models, which optimizes the variational state written as two-dimensional product of tensors. The variational partition function is calculated by the corner transfer matrix renormalization group (CTMRG), which is a variant of the density matrix renormalization group (DMRG). Numerical efficiency of the method is observed via its application to the 3D Ising model. Variational states represented as products of local tensols have been used widely for calculating the ground-state energy in one-dimensional (1D) quantum systems and the free energy in two-dimensional (2D) classical statistical systems. In 1941 Kramers and Wannier calculated a lower bound of the partition function of the 2D
Site energy of the five-state ferromagnetic Potts model is numerically calculated at the first-order transition temperature using corner transfer matrix renormalization group (CTMRG) method. The calculated energy of the disordered phase U+U^{+}U+ is clearly different from that of the ordered phase U−U^{-}U−. The obtained latent heat L=U−−U+L = U^{-} - U^{+}L=U−−U+ is 0.027, which quantitatively agrees with the exact solution.
A variational problem for three-dimensional (3D) classical lattice models is considered with trial state given by two-dimensional (2D) uniform product of local variational weights. This approach, the tensor product variational approach (TPVA), has been applied to 3D classical models (the Ising and the Potts models). We consider a way of estimating the magnetic critical exponent βββ for the simple 3D Ising model assuming a functional form of the spontaneous magnetization in the off critical region, where the TPVA provides reliable data.
The changeover from first-order to second-order phase transitions in q-state Potts models is obtained at q_{c}=2 in spatial dimension d=3 and essentially at q_{c}=4 in d=2, using a physically intuited simple adaptation of the Migdal-Kadanoff renormalization-group transformation. This simple procedure yields the latent heats at the first-order phase transitions. In both d=2 and 3, the calculated phase transition temperatures, respectively compared with the exact self-duality and Monte Carlo results, are dramatically improved. The method, when applied to a slab of finite thickness, yields dimensional crossover.
We consider a variational problem for three-dimensional (3D) classical lattice models, where the trial state is given by a uniform 2D product of local factors. Maximization of the variational partition function draws a self-consistent equation for the local factor. We propose a stable algorithm to solve the equation numerically when the variational function contains many degrees of freedom. Numerical stability and efficiency of the new algorithm is examined through its application to the 3D Ising model. 1